Internal-combustion engine



A. R. PETTERSON.

ENTERNAL COMBUSTION ENGINE.

APPLICATION HLED FEB. 20, I920 Patented Nov. 2, 1920.

UNITED STATES PATENT OFFICE.

ARTHUR R. PETTERSON, 0F WORCESTER, MASSACHUSETTS.

INTERNAL-COMBUSTION ENGINE.

Specification of Letters Patent.

Patented Nov. 2, 1920.

Application filed February 20, 1920.. Serial No. 360,254.

To all til/t0), it may concern:

much reduced.

Reference is to be hadto the accompanying drawings, in which Figure 1 is a side elevation of an eight cylinder engine constructed in accordance with this invention, and

Fig. 2 is a central sectional view of one pair of these cylinders on the line 22 of Fig. 1 on enlarged scale. L

The invention is shown in a form in which the main cylinder 10 of each pair is mounted on the casing 11 in the usual position. The usual crank shaft 12 and connecting rod 13 are employed; also the usual eccentric shaft 14., valve rod 15, and inlet valve 16. The magneto connection 18 is shown in the usual position. The outlet valve for this cylinder does not show but is located in the usual position.

The addition to the features described the cylinder 10 and its connected parts are employed to support a second cylinder 20. This may be cast integrally with the cylinder 10 if desired as shown in the drawings.

The piston 19 which operates in the cylin der 10 is provided with a second rod 23 which passes through a stuliing box 22 in the bottom of a lining 21 fixed inthe cylinder 20. This rod is securely fixed to-the piston 19 and reciprocates with it obviously. It is provided with a piston 29 operating in the lining. The lining is used to facilitate the boring of the cylinder 10 and to provide an immovable solid wall at the bottom between the two cylinders. Inside the casing 11 there is a second eccentric shaft 24 operating an inlet valve rod 25 which directly operates the inlet valve 26 for the upper cylinder and has a battery connection 28 connected up in the usual way. A cover 30 is provided and shown as having a curved pro- I creasing the length of the engine,

' jection 31 extending down to holdthe end of the lining.

In Fig. l, I have shown four of these palrs of cylinders, so that an eight-cylinder englneis-secured without even minutely inand only increasing its height about thirty per cent. In this figure the outlet valves 86 for the upper cylinders are shown.

. in the operation the valves are so set that as the partsstart on the downward stroke the. piston 29 will draw in a charge while 7 the. charge already previously compressed in the space 17 will beexploded and the power Wlll be received from this explosion and end of this stroke of course the two pistons start back simultaneously, the piston 19 acting at that time to force out or exhaust the spent gases while the piston 19 ismaking its compression stroke. downward motionthe gases thus compressed in the space 27 are exploded and the power is received from the upper cylinder, while the lower piston 19 drawing its change of new gas into the space 17. v

As the piston29 descends the air in the lining is compressed by it, but no work is lost because it expands on the upward Then on the second.

. transmitted through the piston 19. At the stroke and assists in moving the pistons up,

thus helping to balance the weight.

In this way increased efficiency is secured and a reduction in the relative amount of space, mechanism, and machine work is also obtained. Simply by practically doubling the length of the cylinder 10, adding the piston 29 and rod 23, providing a lining 21 in the second cylinder 20, and duplicating the sparking connections and the valve mechanism as used on some engines, an engine with two cylinders can be provided giving double the power without correspondingly increasing the space occupied,

and witiout increasing certain features at all. F or example, the crank shaft 12 and rod 13 are not increased in number or even in size so that a material economy in space is secured in this way. Furthermore, the

valve connections do not add materially to the space occupied, and the mechanism for operating them is not of such a nature as to involve much additional expense. The pressure on the crank shaft is made more nearly constant. than usual because each stroke involves a working stroke instead of each alternate one.

No methods of water or air cooling or of lubricating the pistons have been shown as the usual methods can be employed with this invention.

Although I have illustrated and described this invention as applied only to a single type of internal combustion engine and shown the details of construction usually employed in connection therewith, I am aware of the fact that modifications can be made therein and that it can be applied to other types of internal combustion engines, even the two cycle type, without departing from the scope of the invention as expressed in the claims. Therefore I do not wish to be limited in these respects, but -.what I do claim is 1. In an internal combustion engine, the combination of a single crank shaft, a pair of cylinders arranged axially in alinement end to end, a piston in one of said cylinders connected with the crank shaft, a piston in the other cylinder rigidly connected with the first named piston, a lining in the outer cylinder for receiving that piston, a cover having means for holding the lining fixed in its cylinder, and valve connections set to provide for introducing a charge into the lower cylinder during the inward stroke while a charge in the upper cylinder is being exploded and the working stroke is taking place.

2. In an internal combustion engine, the combination of a crank shaft, a pair of cylinders arranged axially in alinement, a liningin the outer one having an end providing a solid immovable wall between said cylinders, a piston in one of said cylinders connected with the crank shaft, a piston in the lining in the other cylinder connected with the first named piston, through the end of the lining, and valve connections for introducing a charge into one cylinder during the inward stroke while a charge in the other cylinder is being exploded and the working stroke in said other cylinder is taking place.

3. In an internal combustion engine, the combination of a pair of cylinders arranged in alinement, a piston in each cylinder, one of said cylinders having a lining extending throughout its length in which its piston operates, said lining being provided with a solid end wall having a packed bearing, and a rod directly connecting the two pistons and operating'in said bearing.

4. In an internal combustion engine, the combination of a crank shaft, a pair of cylinders arranged axially in alinement, a lining in one of said cylinders having a closed end, a piston in one of said cylinders connected with the crank shaft, a piston in the other cylinder connected with the first named piston, and valve connections whereby as the pistons descend one will compress air in the linin which expands on the upward stroke to Iielp lift the pistons.

In testimony whereof I have hereunto affixed my signature.

ARTHUR R. PETTERSON. 

